Semiconductor integrated circuit fabrication facilities (“fabs”) are highly automated. Movement of semiconductor wafers between various process tools is accomplished by an automated material handling system (AMHS). The wafers are typically transported through the fab in Front Opening Unified Pods (FOUPs), wafer holding devices capable of holding up to 25 wafers of 300 mm diameter.
A FOUP is a specialized enclosure designed to hold semiconductor wafers securely and safely in a controlled environment, and to allow the wafers to be removed for processing or measurement by tools equipped with appropriate load ports and robotic handling systems. Slots in the FOUP hold the wafers in place, and a front opening door allows robot handling mechanisms to access the wafers directly from the FOUP. A FOUP can be located on a load port, and can be manipulated by the AMHS.